2.1.3 Amount of substance

• What is the amount of substance?

  the quantity that has moles as its units, used as a way of counting

  atoms.
• What is meant by anhydrous?

  A crystaline compound containing no water
• What is atom economy?

  a measure of the amount of starting materials that end up as useful

  products. A high atom economy means a process is more sustainable as there is less waste produced
• what is the avogadro constant?

  the number of particles per mole of substance (6.02 x 10^23)
• What is meant by the composition by mass?

  the relative mass of each element in a compound.
• What is meant by the empiical formula?

  The empirical formula represents the simplest ratio of elements in a compound.
• What is meant by hydrated?

  A crystaline compound that contains water
• What is menat by an ideal gas?

  a gas which has molecules that occupy negligible space with no interactions

  between them
• What is meant by the molar gas volume?

  The volume of one mole of gas
• What is meant by molar mass?

  The mass of one mole of a substance.
• what is a mole (mol)?

  The amount of any substance containing as many particles as there are carbon atoms in exactly 12g of the carbon-12 isotope
• what is meant by percentage yield?

  the percentage ratio of the actual yield of product from a reaction

  compared with the theoretical yield.
• What is meant by the molecular formula?

  The molecular formula represents the number and types of atoms in a molecule.
• What is meant by the relative molecular mass?

  the average mass of one molecule of an element or compound

  compared to 1/12th the mass of an atom of carbon-12
• What is stoichiometry?

  The relative quantities of substance in a reaction
• What is meant by water of crystalliation?

  water molecules that form part of the crystalline structure of a

  compound
• What is meant by concentration?

  the amount of solute (in mol) dissolved per 1dm^3 of solution.